In this meta-analysis, we sought to examine the ‘active ingredients’ (or behavior change techniques; BCTs) used within theory-based physical activity interventions compared to interventions with no stated theory. We retrieved 171 peer-reviewed studies (224 total interventions) that used a controlled experimental design from 68 previous reviews of physical activity interventions. Data from each intervention were coded with regard to their use of theory and inclusion of 16 BCT clusters within the physical activity intervention. There were no significant differences in the overall effect sizes between theory-based (k = 148, d = 0.48) and no-stated-theory (k = 77, d = 0.37) interventions. Theory-based interventions incorporated a greater number of BCT clusters on average (6.1) compared to no-stated-theory interventions (4.5). Significant effects were shown for interventions that incorporated at least three BCT clusters (d = 0.48) but not for those that used one or two (d = 0.20). Several BCT clusters were more likely to be present in theory-based interventions than no-stated-theory interventions. Significant effects on physical activity were also shown for theory-based interventions that incorporated any of the 16 BCT clusters coded, but only for 9 out of 11 no-stated-theory interventions in this regard (for which effect sizes could be calculated). Taken together, these findings suggest that although the overall effects on physical activity do not differ significantly between theory-based and no-stated-theory interventions, these interventions often differ in their composition of BCTs. Moreover, for interventions utilizing certain BCT clusters (namely, ‘self-belief’ and ‘association’), theory may be necessary to derive significant effects.

Several interventions have targeted dyads to promote physical activity (PA) or reduce sedentary behaviour (SB), but the evidence has not been synthesised. Sixty-nine studies were identified from MEDLINE, PsycINFO, and Web of Science, and 59 were included in the main meta-analyses (providing 72 independent tests). Intervention details, type of dyadic goal, participant characteristics, and methodological quality were extracted and their impact on the overall effect size was examined. Sensitivity analyses tested effect robustness to (a) the effects of other statistically significant moderators; (b) outliers; (c) data included for participants who were not the main target of the intervention. Dyadic interventions had a small positive, highly heterogeneous, effect on PA g = .203, 95% CI [0.123–0.282], compared to comparison conditions including equivalent interventions targeting individuals. Shared target-oriented goals (where both dyad members hold the same PA goal for the main target of the intervention) and peer/friend dyads were associated with larger effect sizes across most analyses. Dyadic interventions produced a small homogeneous reduction in SB. Given dyadic interventions promote PA over-and-above equivalent interventions targeting individuals, these interventions should be more widespread. However, moderating factors such as the types of PA goal and dyad need to be considered to maximise effects.

Affective judgments (AJ; i.e., thoughts about the overall pleasure/displeasure, enjoyment, and feeling states expected from enacting a behavior) have been linked reliably to physical activity (PA) in observational research and feature in various theoretical frameworks. The purpose of this meta-analysis was to examine the current effectiveness of interventions to change AJ and subsequent PA behavior and explore potential moderators. Eligible studies were published in a peer-reviewed journal in the English language, included an experimental design in the PA domain with a measure of AJ as the dependent variable, and were conducted with an adult (>17 yrs.) sample. Literature searches concluded in July 2017 using 11common data-bases, with additional hand searching conducted in February 2018. The search yielded 32 independent studies after screening for eligibility criteria. Results using random-effects meta-analysis showed positive changes in AJ favoring intervention over control groups g = 0.43 (95% CI = 0.26–0.60). These changes predicted (β = 0.64) positive changes in PA g = 0.38 (95% CI = 0.16–0.60) among a sub-sample (k = 14) of studies that also provided behavioral data. Moderator analyses showed the effects were inflated by potential publication bias, participant gender (females had higher AJ than mixed samples), baseline PA (larger effects for inactive samples) and focus of the intervention (larger effects when AJ was the primary focus), but specific behavior change techniques were inconclusive. AJ may show change from experimental intervention and meaningful links to behavior change but larger sample studies are required to obtain a more reliable effect size estimate. Further, few studies have employed behavior change techniques that would align with the theoretical reasons for changes in AJ so our evidence for practical intervention content is limited.

Computer-tailored interventions, which deliver health messages adjusted based on characteristics of the message recipient, can effectively improve a range of health behaviors. Typically, the content of the message is tailored to user demographics, health behaviors and social cognitive factors (e.g., intentions, attitudes, self-efficacy, perceived social support) to increase message relevance, and thus the extent to which the message is read, considered and translated into attitude and behavior change. Some researchers have suggested that the efficacy of computer-tailored interventions may be further enhanced by adapting messages to suit recipients’ need for cognition – a personality trait describing how individuals tend to process information. However, the likely impact of doing so, especially when tailored in conjunction with other variables, requires further consideration. It is possible that intervention effects may be reduced in some circumstances due to interactions with other variables (e.g., perceived relevance) that also influence information processing. From a practical point of view, it is also necessary to consider how to optimally operationalize and measure need for cognition if it is to be a useful tailoring variable. This paper aims to facilitate further research in this area by critically examining these issues based on relevant theories and existing evidence.

Consistent with the common-sense model of self-regulation, illness representations are considered the key to improving health outcomes for medically unexplained symptoms and illnesses (MUS). Which illness representations are related to outcomes and how they are related is not well understood. In response, we conducted a meta-analysis of the relationship between illness representations, self-management/coping, and health outcomes (perceived disease state, psychological distress, and quality of life) for patients with MUS. We reviewed 23 studies and found that threat-related illness representations and emotional representations were related to worse health outcomes and more negative coping (moderate to large effect). Generally, increases in negative coping mediated (with a moderate to large effect) the relationship of threat/emotional illness representations and health outcomes. Protective illness representations were related to better health outcomes, less use of negative coping and greater use of positive coping (small to moderate effect). The relationship of protective illness representations to better health outcomes was mediated by decreases in negative coping (moderate to large effect) and increases in positive coping (moderate effect). Perceiving a psychological cause to the MUS was related to more negative health outcomes (moderate to large effect) and more negative emotional coping (small effect). The relationship of perceiving a psychological cause and more negative health outcomes was mediated by increases in negative emotional coping. Improving our understanding of how illness representations impact health outcomes can inform efforts to improve treatments for MUS. Our results suggest behavioural treatments should focus on reducing threat-related illness representations and negative coping.

This article explores the potential of complex adaptive systems (CAS) theory to inform behaviour change research. A CAS describes a collection of heterogeneous agents interacting within a particular context, adapting to each other’s actions. In practical terms, this implies that behaviour change is (1) socially and culturally situated; (2) highly sensitive to small baseline differences in individuals, groups, and intervention components; and (3) determined by multiple components interacting ‘chaotically’. Two approaches to studying CAS are briefly reviewed. Agent-based modelling is a computer simulation technique that allows researchers to investigate ‘what if’ questions in a virtual environment. Applied qualitative research techniques, on the other hand, offer a way to examine what happens when an intervention is pursued in real-time, and to identify the sorts of rules and assumptions governing social action. Although these represent very different approaches to complexity, there may be scope for mixing these methods – for example, by grounding models in insights derived from qualitative fieldwork. Finally, I will argue that the concept of CAS offers one opportunity to gain a deepened understanding of health-related practices, and to examine the social psychological processes that produce health-promoting or damaging actions.

Studies investigating attentional biases towards pain information vary widely in both design and results. The aim of this meta-analysis was to determine the degree to which attentional biases towards pain occur when measured with the dot-probe task. A total of 2168 references were screened, resulting in a final sample of 4466 participants from 52 articles. Participants were grouped according to pain experience: chronic pain, acute pain, anticipating experimental/procedural pain, social concern for pain, or healthy people. In general, results revealed a significant, but small bias towards pain words (d = 0.136), and pain pictures (d = 0.110) in chronic pain patients, but not in those with acute pain, those anticipating pain, or healthy people. Follow-up analyses revealed an attentional bias towards sensory pain words in the chronic pain group (d = 0.198), and the acute pain group (d = 0.303), but not other groups. In contrast, attentional biases towards affective pain stimuli were not significant for any pain groups. This meta-analysis found support for attentional biases towards sensory pain stimuli in patients with chronic pain in comparison to healthy individuals across a range of common parameters. Future researchers need to consider task design when seeking to optimally measure pain-relevant attentional biases.

Research on the Commonsense Self-Regulation Model has emphasised reflective/conscious perceptual processes regarding illness threat (beliefs about symptoms, consequences, timeline, and curability) in predicting and changing coping behaviours. Understanding of illness self-regulation and avenues for intervention might be enriched by consideration of automatic processes that influence the recognition and identification of illness, response to illness, and ongoing management. This article adopts an integrative approach to (1) outline the theoretical importance of implicit processes in patients’ self-regulation of illness and methods to study them; (2) review research evidence for these processes, including interventions tested to modify them; and (3) outline avenues for future research. A substantial body of research on implicit processes (cognitive bias and interpretational bias) in illness maintenance in chronic illness has recently been extended to detection and interpretation of acute illness and new perspectives relating to the self-system. There is encouraging evidence that cognitive accessibility of coping and implicit attitudes may impact upon coping behaviours. Procedures that strategically automatise coping responses and create habits have considerable promise. We outline an agenda for future research in which health psychology accepts the challenge posed by the interplay of the reflective and associative systems in promoting effective self-regulation of illness.

The aim of this meta-analysis was to quantify the direction and strength of associations between the Consideration of Future Consequences (CFC) scale and intended and actual engagement in three categories of health-related behaviour: health risk, health promotive, and illness preventative/detective behaviour. A systematic literature search was conducted to identify studies that measured CFC and health behaviour. In total, 64 effect sizes were extracted from 53 independent samples. Effect sizes were synthesised using a random-effects model. Aggregate effect sizes for all behaviour categories were significant, albeit small in magnitude. There were no significant moderating effects of the length of CFC scale (long vs. short), population type (college students vs. non-college students), mean age, or sex proportion of study samples. CFC reliability and study quality score significantly moderated the overall association between CFC and health risk behaviour only. The magnitude of effect sizes is comparable to associations between health behaviour and other individual difference variables, such as the Big Five personality traits. The findings indicate that CFC is an important construct to consider in research on engagement in health risk behaviour in particular. Future research is needed to examine the optimal approach by which to apply the findings to behavioural interventions.

Interventions to minimise, reverse or prevent the progression of frailty in older adults represent a potentially viable route to improving quality of life and care needs in older adults. Intervention methods used across European Innovation Partnership on Active and Healthy Ageing collaborators were analysed, along with findings from literature reviews to determine ‘what works for whom in what circumstances’. A realist review of FOCUS study literature reviews, ‘real-world’ studies and grey literature was conducted according to RAMESES (Realist and Meta-narrative Evidence Synthesis: Evolving Standards), and used to populate a framework analysis of theories of why frailty interventions worked, and theories of why frailty interventions did not work. Factors were distilled into mechanisms deriving from theories of causes of frailty, management of frailty and those based on the intervention process. We found that studies based on resolution of a deficiency in an older adult were only successful when there was indeed a deficiency. Client-centred interventions worked well when they had a theoretical grounding in health psychology and offered choice over intervention elements. Healthcare organisational interventions were found to have an impact on success when they were sufficiently different from usual care. Compelling evidence for the reduction of frailty came from physical exercise, or multicomponent (exercise, cognitive, nutrition, social) interventions in group settings. The group context appears to improve participants’ commitment and adherence to the programme. Suggested mechanisms included commitment to co-participants, enjoyment and social interaction. In conclusion, initial frailty levels, presence or absence of specific deficits, and full person and organisational contexts should be included as components of intervention design. Strategies to enhance social and psychological aspects should be included even in physically focused interventions.

Most health behaviour intervention efforts are adapted from the typical psychological treatment experience and may not take into serious consideration theories specifically developed to describe the process of adaptation to illness. This paper presents a proposal for the combination of a theory about the experience of and adaptation to illness, that is, the Common Sense Model of Self-Regulation (CSM), and an efficient psychological theory and therapy, Acceptance and Commitment Therapy (ACT). Past combinations of CSM with cognitive or cognitive-behavioural interventions have focussed almost only on specific aspects of this model (mostly, illness representations and action plans) and left out other, equally important for a fruitful adaptation to illness, recommendations of the model (e.g., regarding the system coherence). Therefore, the development of the proposed combination is to try to match a broad array of the CSM aspects with the principles, intervention techniques and methods employed by ACT, in order to produce a ‘double-pillared’ intervention strategy that may prove especially effective for promoting patients’ adaptation to a chronic condition and enhancing their well-being and health.

Use of fear appeals assumes that when people are emotionally confronted with the negative effects of their behaviour they will change that behaviour. That reasoning is simple and intuitive, but only true under specific, rare circumstances. Risk perception theories predict that if people will experience a threat, they want to counter that threat. However, how they do so is determined by their coping efficacy level: if efficacy is high, they may change their behaviour in the suggested direction; if efficacy is low, they react defensively. Research on fear appeals should be methodologically sound, comparing a threatening to a non-threatening intervention under high and low efficacy levels, random assignment and measuring behaviour as outcome. We critically review extant empirical evidence and conclude that it does not support positive effects of fear appeals. Nonetheless, their use persists and is even promoted by health psychology researchers, causing scientific insights to be ignored or misinterpreted.

Low self-control is associated with increased consumption of alcohol, tobacco, and unhealthy food. This systematic review aimed to assess whether individual differences in self-control modify the effectiveness of interventions to reduce consumption of these products, and hence their potential to reduce consumption amongst those whose consumption is generally greater. Searches of six databases were supplemented with snowball searches and forward citation tracking. Narrative synthesis summarised findings by: consumption behaviour (alcohol, tobacco, food); psychological processes targeted by the intervention (reflective, non-reflective, or both); and study design (experiment, cohort, or cross-sectional). Of 54 eligible studies, 22 reported no evidence of modification, 18 reported interventions to be less effective in those with low self-control, and 14 reported interventions to be more effective in those with low self-control. This pattern did not differ from chance. Whilst self-control often influenced intervention outcomes, there was no consistent pattern of effects, even when stratifying studies by consumption behaviour, intervention type, or study design. There was a notable absence of evidence regarding interventions that restructure physical or economic environments. In summary, a heterogeneous, low-quality evidence base suggests an inconsistent moderating effect of low self-control on the effectiveness of interventions to change consumption behaviours.

The General Health Questionnaire (GHQ-12) is a popular measure of psychological distress. Despite its widespread use, an ongoing controversy pertains to its internal structure. Although the GHQ-12 was originally constructed to capture a unitary construct, empirical studies identified different factor structures. Therefore, this study examined the dimensionality of the GHQ-12 in two independent meta-analyses. The first meta-analysis used summary data published in 38 primary studies (total N = 76,473). Meta-analytic exploratory factor analyses identified two factors formed by negatively and positively worded items. The second meta-analysis included individual responses of 410,640 participants from 84 independent samples. Meta-analytic confirmatory factor analyses corroborated the two-dimensional structure of the GHQ-12. However, bifactor modelling showed that most of the variance was explained by a general factor. Therefore, subscale scores reflected rather limited unique variance. Overall, the two meta-analyses demonstrated that the GHQ-12 is essentially unidimensional. It is not recommended to use and interpret subscale scores because they primarily reflect general mental health rather than distinct constructs.

Researchers have speculated that sedentary behaviour may reduce health-related quality of life (HRQOL), but the extent to which this is true remains unknown. Our study sought to systematically review and synthesise research on the relationship between sedentary behaviours and HRQOL and to investigate if these relationships are moderated by age, health status, and HRQOL domain. The review was registered with PROSPERO (no. CRD42016036342). We searched six electronic databases. The selection process resulted in including k = 27 original studies; k = 18 were included in a meta-analysis. Data were synthesised twice, using the methods of systematic review and meta-analysis, in order to reduce biases related to a small number of included studies. Both the systematic review and meta-analytical methods indicated that lower levels of sedentary behaviours were associated with higher physical HRQOL (estimate of average effect: r = −.140; 95% CI −.191, −.088). Moderator analyses indicated that associations between the physical HRQOL domain and sedentary behaviours may be similar in strength across age- and health status groups. Causal inferences could not be drawn as most studies were cross-sectional. Concluding, sedentary behaviours were related to better physical HRQOL but not reliably to mental and social HRQOL.